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Acta Psychopathologica
ISSN 2469-6676
2016
Vol. 2 No. 6: 45
DOI: 10.4172/2469-6676.100071
From “What” to “How”: The Effort to Fill the
Gaps in Understanding Cognitive Processes
Underpinning Remission in Schizophrenia
Thais Rabanea-Souza and
Acioly Luiz Tavares de
Lacerda
Department of Psychiatry and Medical
Psychology, Federal University of Sao
Paulo, Sao Paulo, Brazil
Abstract
Introduction: The accumulation of robust evidence culminated in the establishment
of the cognitive deficits as a core symptom of Schizophrenia (SCZ). To date,
there has been reliable evidence that cognitive deficits are associated with poor
symptomatic outcomes in SCZ. Nevertheless, they have not been incorporated
in definitions of remission and a systematic understanding of how cognition
contributes to remission is still lacking. Although the standardized remission in
SCZ criteria proposed in 2005 has encouraged studies to understand the role of
cognitive function in symptomatic remission from SCZ, most investigations were
cross-sectional and have studied samples of chronically ill patients. The purpose of
the present study was to bring together the efforts of recent follow-up studies in
early in earlier stages of the disease to fill the gap in the literature on understanding
how cognitive impairment is related to remission.
Methods: A comprehensive search of the PsycINFO and MEDLINE/PUBMED
databases was conducted.
Results: One study evaluated executive functioning in Early-Onset Schizophrenia
(EOS) across stages of illness and suggested that executive impairment is present
at the onset of SCZ and persists in attenuated but stable form after the resolution
of psychotic symptoms. Studies in first-episode schizophrenia (FES) patients
highlighted that despite verbal memory performance is strongly related to clinical
remission in FES spectrum, it appears to have not a meaningful contribution to
functional recovery. Longitudinal studies in SCZ patients suggested that executive
function and higher premorbid Intelligence Quotient (IQ) were the best predictors
of remission.
Corresponding author:
Thais Rabanea-Souza

[email protected]
Researcher at the Interdisciplinary
Laboratory of Clinical Neurosciences,
Department of Psychiatry and Medical
Psychology, Federal University of Sao Paulo,
Brazil.
Tel: +11 46129513, +11 995661628
Citation: Rabanea-Souza T, de Lacerda ALT.
From “What” to “How”: The Effort to Fill the
Gaps in Understanding Cognitive Processes
Underpinning Remission in Schizophrenia.
Acta Psychopathol. 2016, 2:6.
Conclusion: Since were emphasized the need to conduct longitudinal follow-up
studies to assess the relation of cognitive performance to the proposed remission
criteria, some efforts have been made to fill the gaps in understanding cognitive
processes underpinning remission in schizophrenia. Notwithstanding the question
regarding how aspects of symptomatic remission affect, and are affected by,
aspects of cognitive function, remain not yet clarified, these long-term prospective
studies addressing different domains of neurocognition in schizophrenia patients
undergoing remission, mainly in early stages of illness, are being very enlightening
to guide and encourage new researches.
Keywords: Schizophrenia; Remission; Cognitive function
Received: September 19, 2016; Accepted: November 22, 2016; Published: December
01, 2016
Introduction
This disappointment encouraged the search for other factors
that could be related to functional improvements [1]. Actually,
schizophrenia is characterized by significant heterogeneity in
outcome and the last decades have witnessed a significant interest
in identifying factors that can moderate or influence clinical and
functional outcomes in people diagnosed with schizophrenia and
several markers were associated with a poor outcome, which
include: Being male, having a younger age of onset, poorer insight,
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Acta Psychopathologica
ISSN 2469-6676
longer duration of untreated psychosis, poorer premorbid social
adjustment, and higher negative symptoms [2]. In this context,
cognition emerged as a promising marker, and numerous studies
have showed that cognitive functions are strongly correlated and
are an important determinant of outcome in SCZ [1].
Recently, disturbed processing in cognition was considered a
fundamental symptom of schizophrenia, with mild cognitive
deficits appearing well before the onset of psychosis, followed
by a sharp decline in functioning, at or near of First-Episode
Psychosis (FEP), that remains into chronic stages [2]. Thus, besides
the positive and negative symptoms, cognitive impairment is also
an important key feature of schizophrenia and often pre-dates
the disorder [3]. Cognition must be considered in the future
research to overcome the lack of progress in our understanding of
schizophrenia and to the development of adequate treatments,
which cognitive deficits should be central to any guidelines [4].
Against the background of many advances in the treatment of
schizophrenia over the past 50 years, the outcome for many
patients remain poor, and the majority of patients still experience
persistent incapacitating symptomatology and multiple relapses
during the course of the illness [5,6]. In the search for the
potential markers of outcome in schizophrenia, the findings have
contributed to identify the factors, such as cognition, and to
answer the question about “what” is related to outcome, but the
question “how” remains unclear.
To date, there has been reliable evidence that cognitive deficits
are associated with poor symptomatic outcomes in schizophrenia
[7]. Nevertheless, they have not been incorporated in definitions
of remission [5]. A systematic understanding of how cognition
contributes to remission is still lacking. The purpose of this
paper is to review recent research into the relationship between
cognitive deficits and symptomatic remission. All selected
studies were published after the introduction of the consensus
definition for remission in SCZ proposed in 2005 by the Remission
in Schizophrenia Working Group (RSWG). According to RSWG,
symptomatic remission is achieved when the following criteria
is fulfilled: Mild severity (score of 3 or lower) in 8 items of the
Positive and Negative Symptoms Scale Positive and Negative
Symptoms Scale (PANSS) (e.g., delusions, unusual thought
content, hallucinatory behavior, mannerisms/posturing, blunted
affect, social withdrawal, lack of spontaneity). There is also a
minimum time threshold of 6 months in which the symptoms of
severity must be maintained [5,8].
The standardized remission criteria has encouraged studies
to understand the role of cognitive function in symptomatic
remission from schizophrenia, however most investigations
were cross-sectional and have studied samples of chronically
ill patients. Taken together, the results from these previous
studies there were no clear evidence whether cognitive ability
is a contributing factor for achieving remission. Although
cognitive performance was identified as a predictor of outcome
in schizophrenia [9] was not assessed in follow-up studies in the
relation to the proposed remission criteria [8]. Therefore, the
nature of how aspects of symptomatic remission affect, and are
affected by, aspects of cognitive function remains unclear. More
recently, we have witnessed an increase of longitudinal studies in
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Vol. 2 No. 6: 45
earlier stages of the disease and the present systematic review
brings together the efforts of recent studies to fill the gap in the
literature on understanding how cognitive impairment is related
to remission.
Search Strategy
A comprehensive search of the PsycINFO and MEDLINE/
PUBMED databases was conducted. Within the domain of
cognitive systems, the following search terms were used: (1)
Neurocognition/cognitive function; (2) Attention; (3) Memory;
(5) Speed of processing; (4) Executive functions. Within the
domain of symptomatic remission, the following terms were
used: (1) Symptomatic remission; (2) Symptomatic patients.
Search terms for schizophrenia included the following: (1) Earlyonset schizophrenia; (2) First-episode schizophrenia/first-episode
psychosis; and (3) Chronic schizophrenia.
The results from these searches were assessed for eligibility
using the following hierarchical criteria: (1) Studies were peerreviewed original articles published in English; (2) Participants
had a diagnosis of schizophrenia according to the Diagnostic and
Statistical Manual of Mental Disorders (DSM) criteria or to the
International Classification of Diseases (ICD) criteria; (3) Symptom
severity was assessed by means of the Positive and Negative
Symptoms Scale (PANSS) and to assess remission, the majority
of the studies have used the criteria proposed by Andreasen et
al. [5], according to which 8 items of PANSS (delusions, unusual
thought content, hallucinatory behavior, mannerisms/posturing,
blunted affect, social withdrawal, lack of spontaneity) should
be scored ≤3 (mild) for at least 6 months; (4) The groups were
compared using statistical techniques; (5) The research method
used was a longitudinal study; (6) Published after 2010.
Early-Onset Schizophrenia (EOS)
Early-Onset Schizophrenia (EOS) is considered to be the most
severe form of the disease, fortunately is extremely rare.
Schizophrenia onset before age of 18 years old is strongly
associated with higher morbidity and mortality risks for children
and adolescents. Because of the interplay between genetic and
environmental risk factors, this form of schizophrenia seems to
have meaningful neurodevelopmental components which are
associated with a correspondent cognitive process development
[10].
Remberk et al. [11], evaluated executive functioning, using
Wisconsin Card Sorting Test (WCST), in EOS across stages of
illness. Hospitalized EOS subjects (aged 13-18) with first episode
at the introduction of pharmacotherapy (FES T1) and after
the resolution of psychotic symptoms at psychopathological
symptoms mean 7 weeks (FES T2) and Stable Outpatients (SO)
group (aged 16-19 with diagnosis of early-onset schizophrenia,
with at least one previous hospitalization and illness duration of
minimum one year) were matched with healthy controls. Severity
of symptoms was assessed with Positive and Negative Syndrome
Scale (PANSS), total score and positive, negative and general
psychopathology subscales scores were analyzed, however
any formalized definition of remission was applied. The results
showed that patients performed significantly worse in WCST than
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Acta Psychopathologica
ISSN 2469-6676
healthy controls, however FES T1 presented more pronounced
executive impairment and psychopathological symptoms than
FES T2 and SO, between which no differences were observed,
suggesting that executive impairment is present at the onset of
schizophrenia and persists in attenuated but stable form after the
resolution of psychotic symptoms.
First-Episode Psychosis/Schizophrenia
Chronic schizophrenia patients have generally long histories
of multiple episodes of psychosis and treatment, thus the
neurocognition dysfunctions widely observed are likely to be
influenced by effects of age, clinical symptoms, illness duration
and severity, which emphasizes the need for studies of young and
first-episode patients. While most the majority of first-episode
schizophrenia patients may be able to achieve and maintain a
remission of symptoms, the overall rate of recovery during the
early years of the disease is very low: Only one in seven are likely
to meet criteria for recovery [6,12].
Torgalsbøen et al. [13], conducted a long-term prospective
study of first-episode schizophrenia patients (FES) assessing
the relationship between neurocognition and remission in firstepisode schizophrenia patients with follow-up points at baseline
and after 6 months. Their results showed that more than half
of the group of first-episode patients where in remission,
neurocognitive baseline measure of attention (from the MATRICS
Consensus Cognitive Battery) predicted remission status at
follow-up and in the early course of the illness, and remitted
patients had significantly higher scores on overall neurocognitive
function than those not fulfilling the remission criteria.
Chang et al. [14], also examined the longitudinal relationships
between cognitive functioning and symptomatic remission in
first-episode schizophrenia patients. The cognitive functions were
measured at clinical stabilization and at 12, 24 and 36 months.
The findings suggested that verbal memory impairment might be
specifically related to attainment of sustained remission in the
early stage of the illness.
Based on previous investigations on FEP that have isolated
verbal memory as a potential cognitive marker of symptomatic
remission, Benoit et al. [15], designed a study aimed to compare
verbal, visual and working memory performance between
remitted and non-remitted FEP longitudinally. Using the full
RSWG criteria to categorized symptomatic remission, cognition
was evaluated after 3 and 15 months of treatment. The results
suggested that verbal memory might be a specific and stable
marker of clinical remission in FEP patients, corroborating the
findings of Chang et al. [14].
Considering the relevance of symptomatic remission and cognition
for functional outcome, primary goal following treatment of
schizophrenia, Jordan et al. [16], organized a longitudinal study
to investigate the contribution of cognition, in particular verbal
memory, and symptomatic remission to social and occupational
functioning in a sample of first-episode schizophrenia subjects.
They conclude that verbal memory contributed only slightly to
such outcome, while length of remission of negative and positive
symptoms made a large contribution at 2 years. These results
© Under License of Creative Commons Attribution 3.0 License
2016
Vol. 2 No. 6: 45
highlights that despite verbal memory performance is strongly
related to clinical remission in first episode of schizophrenia
spectrum [14,15], it appears to have not a meaningful contribution
to functional recovery.
Bodnar et al. [17], conducted an important study that
shown a strong evidence of the parahippocampal cortex as a
possible neural marker of early remission among first-episode
schizophrenia patients. The results also have showed that nonremitted first-episode schizophrenia patients performed worse
in verbal memory domain and there is a positive correlation
between bilateral parahippocampal cortex volume and verbal
memory performance. These results are in line with Chang et al.
[14], and Benoit et al. [15], but are not confirmed by Torgalsbøen
et al. [13]. Notwithstanding, Torgalsbøen et al. [13] is an outgoing
study, and is recommended to wait for the results from the
next follow-up before drawing conclusions. In addition, chronic
patients with an average (or higher) verbal intelligence appears
to be more likely to reach the status of clinical remission in
schizophrenia [3].
Chronic Schizophrenia
Andreou et al. [7], run a longitudinal study aimed to assess the
contribution of neuropsychological deficits on the probability of
achieving early symptomatic remission after a psychotic episode
in schizophrenia patients. The results suggested that patients who
achieved remission exhibited a significant better performance
on the Trail Making Test Part B (TMT-B), a neuropsychological
instrument of choice to measure executive function, and higher
premorbid Intelligence Quotient (IQ). According to the findings,
TMT-B performances at baseline were the one of the best
predictors of remission.
A polish research group [3] investigated the association of
cognitive deficits and clinical remission at baseline and after
three years. Higher verbal IQ, but not performance intelligence,
was related to a greater chance of remission after three years,
which suggests that patients with an average (or higher) verbal
intelligence, in a non-active phase of the illness are more likely to
reach the status of clinical remission in schizophrenia.
Conclusions and Future Directions
Advances in treatments, a novel understanding of the etiology and
course of schizophrenia, and earlier attention to diagnosis have
led to a shifting on the perspectives surrounding schizophrenia,
improving longer-term outcome potential and encouraging an
increase in emphasis on functional outcome and overall well-being
of schizophrenia patients. Although many improvements have
been made since the introduction of the consensus definition for
remission in schizophrenia proposed in 2005 by the Remission
in Schizophrenia Working Group, this criteria are confined to
dimensions of psychopathology and did not address other domains,
such as cognition, that are critical to functional recovery [18].
Actually, remission is a more defined and achievable goal, a
necessary step but not sufficient toward recovery [19]. The
remission criteria, unlike recovery, implies symptoms that do not
interfere with function, thus people diagnosed with schizophrenia
in remission may continue to be cognitively impaired and
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Acta Psychopathologica
ISSN 2469-6676
marginalized, most because of a poor social functioning [20]. It
has important implications especially for patients, families, directto-consumer advertising, insurance companies, governments,
and societies, because the term remission might bring the
expectation that all explicit signs of the disease are gone and
that the individual is now freed from illness, which contrasts with
reality, frustrating them all [18].
Cognitive functioning has been found to be improved in recovery
[21], and a better cognitive performance was associated with the
adequate social/vocational functioning and symptom remission
components of recovery [12], strengthening the considerable
amount of the evidences that supports the substantial influence
of cognition on functional capacity yielding autonomous everyday
functioning in schizophrenia patients [22,23].
Lepage et al. [2], have explored neurocognitive function in
relation to both clinical and functional outcome, and highlighted
that verbal memory appears to be one of the strongest markers
of outcome. However, despite verbal memory performance
are strongly related to clinical remission in first episode of
schizophrenia spectrum [14,15], it appears to have not a
meaningful contribution to functional recovery [16]. However,
these results differ from some published studies that suggest
that verbal memory deficits might reduce one’s employment
prospects compromising overall functional outcome [24,25].
Remberk et al. [11], bring out that executive impairment is
present at the onset of the disease and persists in attenuated but
stable form after the resolution of psychotic symptoms. These
results are consistent with those of previous literature that have
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2016
Vol. 2 No. 6: 45
noted decline of cognitive functions at the time of onset of clinical
symptoms with partial recovery of cognitive functions during the
stabilization phase after first onset [23].
Andreou et al. [7], emphasized that a better executive
performance seems to predict early symptomatic remission after
a psychotic episode in schizophrenia patients. Some of the earlier
cross-sectional studies have found no significant differences
in executive functioning of fully remitted patients and healthy
controls [26] or of remitted and non-remitted schizophrenia
patients [27]. On other hand, some studies revealed marked
differences in executive functioning between patients who have
met the remission criteria from those who haven´t [25,28]. Taken
together, these findings are in line with prior research, which
identified a little consistent evidence of differential decline in
executive functions in schizophrenia patients [23]. The longterm prospective study referred [7], appears to provide clearer
evidence about the impact of executive functions on symptomatic
remission after an acute episode in schizophrenia patients.
Since Lambert et al. [8], emphasized the need to conduct
longitudinal follow-up studies to assess the relation of cognitive
performance to the proposed remission criteria, some efforts
have been made to fill the gaps in understanding cognitive
processes underpinning remission in schizophrenia. Although
the question regarding how aspects of symptomatic remission
affect, and are affected by, aspects of cognitive function, remain
not yet clarified, these long-term prospective studies addressing
different domains of neurocognition in schizophrenia patients
undergoing remission, mainly in early stages of illness, are being
very enlightening to guide and encourage new researches.
This article is available from: www.psychopathology.imedpub.com
Acta Psychopathologica
ISSN 2469-6676
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